I have MacOS snow leopard and Windows 7 installed on same hard drive(on a iMac). I want to have a folder that is shared between them where I can write data, not only read. Is this possible? On windows partition MacOS says that I don't have permission to write and on Mac partition Windows says same thing.

My answer is simply to format a flash drive to FAT 32 put it into a spare USB Port ( I recommend a 3.0 USB flash drive and 3.0 USB port )You can add to and remove from both drives. I then sync my devices from my Mac boot drive using iTunes.

Why use a flash drive when you have your hard drive inside the computer that both operating systems can access? This is a bad solution and should not be used in this scenario.
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PiccoloAug 26 '14 at 22:38